Two-cycle gas-engine.



o. H.' DUREE. V TWO-CYCLE GAS ENGINE. APPLICATION FILED 0OT.25, 1908.

, Patented June 14, 191C.

Amuvew s. GRAHAM w, Moromuocmawsks, wASmNmoN. u c

PUhlifllii) STATES PATEN T OFFICE.

OSCAR H. DORER, OF IRVINGTGN, NEW JERSEY.

TWG-CYCLE GAS-ENGINE.

To all whom it may concern:

Be it known that I, OSCAR H. Doran, a citizen ot the United States,residing at Irvington, in the county of Essex and State of New Jersey,have invented certain new and useful Tmprovements in Two CycleGas-Engines; and l do hereby declare the following to be a full, clear,and exact description of the invention, such as will enable othersskilled in the art to which it appertains to make and use the same,reference being had to the accompanying drawings, and to figures otreference marked thereon, which form a part ot' this speciiication.

This invention is designed to provide a gas engine or an internalcombustion engine which uses a fuel gas, the engine being a. two-cycleengine and having a fuel eiiiciency and power of production to equal afour-cycle engine. These results are brought about by making a goodmixture in the tuel and by means ot ditlerent mechanisms to behereinafter more fully described.

The gas engine is designed to provide a cylinder, one end ot which isused as a compression chamber, the piston reciprocating to compress theair in the compression chamber, and at the same time being actuated b anexplosive mixture on the other side of the piston. When the power strokeis complete, two exhausts are opened, one being opened by the action otthe piston passing it, and the other being opened mechanically, theseexhausts being at opposite ends of the chamber which is formed by thepiston and the cylinder when the piston is at the end ot its powerstroke. Mechanism is also installed whereby the inlet for the air fromthe compression chamber is opened so that free air is admitted to thechamber formed by the cylnder and the piston, when at the end ot itspower stroke, so that a body ot pure air is injected into this chamberin the cylinder and has a tendency to divide and torce the explodedgases trom this chamber at its two ends, thus thoroughly scavenging thechainber. This operation of cleaning out the cylinder takes place at theend of the stroke, while the crank is going over, and suiiicient time isgiven to force this air from the compression chamber to clean out theexplosion chamber, and the air from the compression chamber picks upfuel gas, when the scavenging is complete, so that an explosive mixtureis admitted to the explosion cham- Speclication of Letters Patent.

Application filed October 26, 3.9%.

Patented June 14, 1910.

Serial No. 459,4'3.

ber after the tree air has cleaned it out, and this mixture is thencompressed to form an explosive mixture that is then ignited by a sparkin the usual manner, and the operation is repeated.

The invention is illustrated in the accompanying drawings, in whichhFigure l is a top view partly in section showing the improved engine.Fig. 2 is a side view of the same broken away in portions to betterillustrate the device, and F ig. 3 is a detail ot the shifting mechanismfor the cams :tor operating the gas inlet and the exhaust of theexplosion chamber. Fig. 4 is a view showing the connection of the fuelpump with the inlet for the fuel vapor. Fig.

5 is a detail showing the means tor operating the mechanically operatedexhaust.

The engine comprises a cylinder l0 which is water-jacketed, as usual inthis class of engine, so as to prevent the heating of the parts. Thecylinder has, operated therein, a piston ll which reciprocates in thecylinder and is provided with a piston rod l2 which is connected in anywell known manner, but preferably by the link 13 with the crank ll oitthe shaft l5 otl the engine, and it is also provided with the usualbalance wheels 1G to steady the motion and carry the engine over. Thepiston, when in the position shown in Figs. l and 2, has completed itscompression stroke and is about to start on its power stroke, theexplosive mixture in the chamber 17 being ignited by any usual form otsparker mechanism 18, and the piston is started on its power stroke, atthe same time compressing the air in the chamber l5). 'Vhen the pistonfinishes its power stroke, the head ot the piston has completelyuncovered the exhaust 2O which is then at one end ot the chamber 1T, thechamber 17 being enlarged by the movement of the piston, and the exhaust2l is opened by a mechanical means to be hereinafter described, theopening being by means of the valve Q2 and simultaneous with theuncovering ot the exhaust Q0. These two exhausts Q0 and 2l are openedfully at the completion of the stroke and give two outlets for thepassage ot the exploded gases from the explosion chamber, which dividesythese gases, and they pass out either end ot the explosion chamber.This is taking place while the crank is going over about thirty degrees4at the end ot its stroke, and in the meantime this outlet,

through two exhausts, has permitted about sixty per cent. of theexploded gases to pass, and this naturally greatly reduces the pressurewhich would necessitate, under normal conditions, a longer time for theremaining gases to pass out. To sweep them from this explosion chamber,the reduction in pressure permits the valve 23 leading into the inletport 24, to be forced open by the air compressed in the chamber 19,which air passes through the channel 25 and through the casing 26 intothe pipe 27, and up past the valve 23 through the port 24 into thecenter of the explosion chamber, that is, about central between the twoexhausts and preferably on the opposite side of the cylinder. This freshair rushing into the explosion chamber forms a body of pure air whichforces both ways toward the exhausts and cleans out the exploded gasesthoroughly. 1t will be understood, however, that it is necessary, assoon as enough pure air has passed into the explosion chamber to formthe body of pure air for scavenging, that fuel vapor be taken, alongwith the remaining air, and fed into the explosion chamber behind thebody of pure air, the whole operation being completed an instant afterthe exhaust-s are closed. Thus, at this instant, an explosive mixturefills the explosion chamber. To accomplish this it is necessary to opena valve 28 which is connected, by suitable piping 29, to a fuel pump 30,shown more particularly in Figs..2 and 4 the valve 28 being normallyheld shut by a suitable spring. This pump is operated by a rod 31 and isa pump of any usual construction, the rod 31 being operated by theeccentric 32, shown in Fig. 1, which is operated by the shaft 33 whichis rotated by means of the spiral gears 34, one of which is attached tothe shaft 33, and the other, to the shaft 15 of the engine. This pump iscontinually operating, butthe admission of fuel vapor thereto isregulated by means of a mechanism to be described hereinafter. The pump30 and the chamber 19 work in harmony, that is, when gas is beingcompressed in the pump, air is being compressed in the chamber, themaximum pressure the gas attains being greater t-han that of the air, inapproximately the ratio of 50 to 33. When about one-sixth of thecompressed air in the chamber 19 and the inlet 24 has been allowed toexpand into the cylinder, the gas admission valve 28 opens, that is,when the pressure of the air in the passage between the compressionchamber 19 and the explosion chamber 17 is reduced, the valve 28 opensbecause the pressure of the gas underneath it is greater than thepressure of the air above it. The fuel gases rush with the air into thecasing 26 and through the pipe 27 through the valve 23 and the inletport 24, and the gas and the air are well mixed and form an explosivemixture that is efficient, said explosive mixture expanding behind thescavenging air as before stated. Thus the whole operation of exhaustingthe exploded gases from, and admitting fresh gases to, the cylindertakes place while the crank is revolving through sixty degrees at theend of the power stroke. The fresh gases replace the exploded gases asthe latter are driven from the explosion chamber, and are prevented frommixing with the exploded gases by the bodies of pure air.

1t is necessary that the valve 28 should close before the valve 23closes, so that all of the explosive mixture will enter the cylinder. 1fthis were not done, some gas would remain in 27 and act with the body ofpure air to scavenge out the exploded gases in the explo-sion chamber,after the next explosion took place. This would be a waste and detractfrom the efficiency of the engine. This particular closing action isinsured by the strength of the springs actuating these valves, and bythe compression which takes place in the inlet port 24, when the pistonpasses up and closes this port previous to the explosion of the gases.The eccentric 32 rotates with the beveled gear 35, which meshes with asecond beveled gear 36, and rotates a shaft 37 which rotates in bearingssecured to the machine frame, and on which is a ball and uprightadjustable spring, or other' suitable governor 38. When the speed of theengine decreases or increases, the governor acts to raise or draw down,as the case may be, an arm 39 Which operates a link 40, which in turnoperates a bell crank 41 which pulls over a bar 42 which is pivotallyconnected with a yoke 43, shown more particularly in Fig. 3. This yokeis connected, by means of the straps 44, to collars 45 and 46 whichrotate with the shaft 33 and are slid along a feather.

To one collar 46 is attached a circumferential step down cam 47 similarto 57 in F ig. 5, against which operates a wheel 48, and a movement ofthis cam along the shaft 33 regulates the outward movement of the wheel48, this wheel being shown more particularly in F ig. 4, and it isattached to a rod 49. The end of this rod is adapted to engage aregulating screw 50 which can be moved toward or from the end of the rod49 by screwing it on the stem 51 of a valve 52 in the casing 53. Thisvalve regulates the admission of fuel gas through the pipe 54, from asource of supply, and said gas then passes through the pipe 55 to thecasing 56, and from there into the pump 30 and through the pipe 29underneath the valve 28 and is admitted, at the proper time, through themeans above quoted. The cam' 47 is so constructed that the valve 52 iskept open during the Whole of the suction stroke of the rod 31, when theengine is running normally, and each step on the cam corresponds to anarc about six degrees less than its preceding step las the engine speedsup, a smaller of the stepped cams engages wheel 48, and keeps valve 52open less time. Therefore less gas is drawn into pump 30 and there willbe less compression to the gas when the piston of pump tlreturns.Therefore valve QS will not be opened so soon, because there is lesspressure underneath it, which permits more air to pass into the bodiesof scavenging air. To accommodate the increase in speed in the engineand to allow for the exhaustion of the larger bodies of scavenging air'the mechanically operated exhaust is kept open longer. This isaccomplished by a circumferential step down 7 cam 57 which is attachedto the collar 45 and which when moved along the shaft 33 regulates thelength of time of the throw of a roller 5S in the end of the arm 59,which arm is pivoted at 60, the other end 61 of which operates the` endof the stem 62 which is attached t0 the valve 22, which is themechanically operated exhaust valve. The steps on 57 are in the oppositedirection to those on 47, and are on the side of the cam correspondingto the closing of the valve Q2. As the -engine speeds up, the exhaustvalve 22 is kept open longer as per 57, while at the same time the gasvalve 52 is kept open less time as before stated. The rotation of 57takes place in the direction indicated by the arrow. These adjustmentsthrough the governor are arranged to bring about the best results bytiming the opening and closing of these valves so that there is aperfect cooperation, and so as to permit of throttling the mixture andkeeping it always of the same strength. Air is admitted to the chamber19 through the inlet valve 63, shown in Fig. 2, at the return of thepiston 11.

Having thus described my invention, what T claim is 1. An internalcombustion engine comprising a cylinder having a piston therein, thecylinder having a pair of exhausts arranged so as to be at the ends ofthe explosion chamber when the piston is at the limit of its powerstroke, the piston uncovering one exhaust at the limit of its powerstroke, means for opening the second exhaust while the first exhaust isuncovered, an air inlet to the cylinder substantially equi-distantbetween the exhausts whereby the admission of air through the inletcleans the explosion chamber from its two ends, and means for supplyingfuel to the air inlet after a portion of the air has passed the fuelsupplying means.

2. An internal combustion engine comprising a cylinder having a pistontherein, the cylinder having a pair of exhausts, the exhausts beingarranged at opposite ends of the explosion chamber when the piston is atthe limit of its power stroke, a compression chamber formed in the endof the cylinder on the opposite side of the piston from the explosionchamber, means for conducting compressed air from the compressionchamber to a point in the explosion chamber substantially equi-distantbetween the exhausts whereby compressed air is admitted to the explosionchamber to force the exhaust from both ends, and means for supplyingfuel to the air inlet after a portion of the air has passed the fuelsupplying means.

3. An internal combustion engine comprising a cylinder having a. pistontherein, the cylinder having a pair of exhausts, one exhaust beingopened by the piston, means for opening the second exhaust when thepiston is at the limit of its power stroke, a compression chamber formedby the piston and the cylinder at the back of the piston, means forconducting compressed air from the compression chamber to the explosionchamber, means for admitting fuel gas to the conducting means, and meansfor governing the quantity of gas admitted to the air conducting means.

4. An internal combustion engine con prising a cylinder having a pistontherein, the cylinder having a pair of exhausts arranged to be at theopposite ends of the explosion chamber when the piston is at the limitof its power stroke, one of the exhausts being opened by the piston,means for opening the second exhaust when the piston is at the limit ofits power stroke, a compression chamber in the cylinder behind thepiston, means for conducting air from the compression chamber to theexplosion chamber after the exhausts have been opened, a fuel pump,means for conducting fuel gas from the pump to the air conducting means,and means for governing the quantity of gas admitted to the airconducting means.

5. An internal combustion engine coinprising a cylinder, a piston in thecylinder, the cylinder having a pair of exhausts, one exhaust beingarranged at one end of the cylinder, and the other exhaust beingintermediate of the ends of the cylinder, the second exhaust beinguncovered by the piston at the limit of its power stroke, mechanicallyoperated means for opening the exhaust at the end of the cylinder whenthe piston is at the end of its power stroke, the cylinder at the backof the piston forming a compression chamber, means for conducting airfrom the compression chamber to a point in the explosion chambersubstantially equidistant between the exhausts, a fuel pump, and meansfor admitting fuel gas to the air conducting means after a portion ofthe pure air from the compression chamber has passed from thecompression chamber to the explosion chamber.

6. An internal combustion engine comprising a cylinder, a piston in thecylinder, the cylinder having a pair of exhausts, means for opening oneexhaust when the piston is at the limit of its power stroke, the otherexhaust being opened by the piston, the cylinder at the back of thepiston forming' a compression chamber, means for conducting' compressedair from the compression chamber to the explosion chamber, a fuel pump,and means for admitting fuel gas to the air conducting means after aportion of the air has passed from the compression chamber toward theexplosion chamber.

7. An internal combustion engine comprising a cylinder, a pistontherein, a pair of exhausts, one exhaust being adapted to be uncoveredby the piston when the piston is at the limit of its power stroke, avalve in the second exhaust, a cam adapted to open said valve when thefirst exhaust is uncovered, the cylinder having an inlet equi-dis tantbet-Ween the exhausts, means for compressing air, means for conductingair from the air compressing means to the air inlet, 25

whereby air is admitted to the explosion chamber to force the exhaustfrom both ends of the explosion chamber, a fuel pump, and means foradmitting fuel gas from the fuel pump to the air conducting means after30 OSCAR H. DORER.

IVitnesses:

E. A. PELL, M. JOHNSON.

